Washing clothes in an industrial setting has many challenges that are not typically encountered in most domestic and commercial settings. For example, in some industrial settings the workers are in contact with machinery on a regular basis, which can make their clothes or uniforms soiled with oils and grease from those machines. In many instances, the clothing can be highly soiled. Accordingly, in certain industrial cleaning settings it is necessary to use more aggressive cleaning conditions as typical detergents, such as basic emulsion detergents, are not able to remove such oils effectively.
One alternative method of dealing with oil and grease that is commonly employed in commercial and domestic settings is the use of soil-release polymers (SRPs). SRPs are polymers that are able to bind to the fibers of clothing and prevent or reduce the amount of soils such as oil and grease from adhering to those fibers. SRPs can be effective at improving the removal of oily soils from synthetic fabrics in a laundry wash process. However, SRPs are not compatible with a typical industrial wash formula due to the highly alkaline main wash step—hydroxide-based alkaline step. Conventional SRPs possess a polyester backbone which is believed to be hydrolyzed in highly alkaline environments. In consumer laundry where the pH is generally near neutral, this is not an issue. But most industrial laundry uses a high alkaline step to help remove and suspend the industrial soils. Within the industry, it is typical to have a high alkaline prewash with hydroxide-based alkali, followed by detergent in a later step (see, for example, Riggs, Charles L. et al., “Bar Mops Formula,” Textile Laundering Technology TSRA Handbook). Therefore, for use in industrial wash processes it would be desirable to use a high alkaline step and a soil release polymer in a way in which it is still effective. There have been attempts to remedy this problem, which have included, for example, in U.S. Pat. No. 6,200,351, the use of SRPs in a prewash step of an industrial washing method. What the '351 patent did not anticipate is that if soil release polymers are used in a prewash step which contains a hydroxide-based alkaline source (caustic alkalinity), the most common alkali used within the industry, the polymers are completely ineffective.
Therefore, there exists a need for improved cleaning compositions that can provide the required high level of cleaning in industrial applications. Further, there is a need to find viable cleaning methods for using SRPs in an industrial wash setting.
Accordingly, it is an objective of the claimed invention to provide a method for removing oily and/or greasy soils in an industrial was setting.
A further object of the invention is to methods of cleaning oily and/or greasy soils with the use of a SRP.
Other objects, advantages and features of the present invention will become apparent from the following specification taken in conjunction with the accompanying drawings.